Question

There are 25 number of cards numbered from 1 to 25 in a box. A card is drawn random , find probability of card. A.
Multiple of 3. B. Multiple of 5. C. Multiple of 3 and 5

Answer 1

1)3,6,9,12,15,18,21,24 = 8 / 25

2) 5,10,15,20,25 = 5 / 25 = 1 / 5

3)8 + 5 = 13 / 25

Answer 2

In the given event, the probability of drawing a card which is a multiple of 3 is 8/25, a multiple of 5 is 1/5, and a multiple of both 3 and 5 is 1/25.

• Given,

Number of cards = 25

Numbers on the cards = 1 to 25

A. Multiples of 3 from 1 to 25 = 3, 6, 9, 12, 15, 18, 21, and 24

=> Number of cards which are a multiple of 3 from 1 to 25 = 8

• Therefore, probability of drawing a card which is a multiple of 3 = Number of cards which are multiples of 3 / Total number of cards

=> Probability = 8/25

B. Multiples of 5 from 1 to 25 = 5, 10, 15, 20, and 25

=> Number of cards which are a multiple of 5 from 1 to 25 = 5

• Therefore, probability of drawing a card which is a multiple of 5 = Number of cards which are a multiple of 5 / Total number of cards

=> Probability = 5/25 = 1/5

C. Multiple of both 3 and 5 from 1 to 25 = 15

=> Number of cards which are a multiple of both 3 and 5 from 1 to 25 = 1

• Therefore, probability of drawing a card which is a multiple of both 3 and 5 = Number of cards which are a multiple of both 3 and 5 / Total number of cards

=> Probability = 1/25